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LSU Doctoral Dissertations

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Articles 1141 - 1170 of 1402

Full-Text Articles in Physical Sciences and Mathematics

Mass Transfer And Evolution Of Compact Binary Stars, Vayujeet Gokhale Jan 2007

Mass Transfer And Evolution Of Compact Binary Stars, Vayujeet Gokhale

LSU Doctoral Dissertations

We present a study of key aspects of the evolution of binary stars with emphasis on binaries consisting of two white dwarf stars. The evolution of such systems is driven by the loss of angular momentum by gravitational wave radiation. Effects like mass transfer and other modes of angular momentum loss and redistribution influence the evolutionary fate of the binary, and can lead to a merger, the tidal disruption of one of the components or its survival as a long-lived AM Canum Venaticorum (AM CVn) type system. Our study takes into account some of these effects; like mass loss, tides, …

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Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett Jan 2007

Investigation Of Phospholipid Tubule Morphology For Use In Drug Delivery, Colleen Colson Garrett

LSU Doctoral Dissertations

Spherical vesicles consisting of phosphatidylcholines in which diacetylene groups have been inserted in the hydrocarbon tail centers give rise to hollow cylindrical tubes, known as “tubules”. The study of tubules has become an area of intense interest in recent years due to their unusual morphology, which raises several profound theoretical issues and suggests their use in a variety of applications. Tubule hollowness suggests medical and industrial encapsulations as well as filtration and purification applications. These potential uses, e.g., for drug and gene delivery, requires optimization of their morphology for the application. Tubules have many technologically desirable properties, such as a …

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Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo Jan 2007

Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo

LSU Doctoral Dissertations

Recent marine and late Pleistocene sediments examined from the Gulf of Papua (GoP), Papua New Guinea investigate the flux and fate of detrital sediments and organic carbon over the last glacial-interglacial cycle. Based on surface sediment magnetic susceptibility (MS) and calcium carbonate concentrations, recent marine sediment is exported off the narrow shelf and into deeper regions via the Kerema Canyon of the northern Pandora Trough. Detrital clastic sediment is then dispersed deeper into the central and southern Pandora Trough. Except for pelagic deposition, very little detrital material reaches the Ashmore Trough and Eastern Plateau adjacent to the Great Barrier Reef. …

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Subrepresentation Semirings And An Analogue Of 6j-Symbols, Nam Hee Kwon Jan 2007

Subrepresentation Semirings And An Analogue Of 6j-Symbols, Nam Hee Kwon

LSU Doctoral Dissertations

Let G be a quasi simply reducible group, and let V be a representation of G over the complex numbers $mathbb{C}$. In this thesis, we introduce the twisted 6j-symbols over G which have their origin to Wigner's 6j-symbols over the group SU(2) to study the structure constants of the subrepresentation semiring S_{G}(End(V)), and we study the representation theory of a quasi simply reducible group G laying emphasis on our new G-module objects. We also investigate properties of our twisted 6j-symbols by establishing the link between the twisted 6j-symbols and Wigner's 3j-symbols over the group G.

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Establishment And Chemical Analysis Of Hairy Roots Of Eucommia Ulmoides, Xiaojun Wu Jan 2007

Establishment And Chemical Analysis Of Hairy Roots Of Eucommia Ulmoides, Xiaojun Wu

LSU Doctoral Dissertations

The bark of Eucommia ulmoides Oliver (Eucommiaceae) has been used over thousands of years as a folk remedy. Extracts from the bark exhibit multiple pharmacological functions, especially in lowering blood pressure. Geniposidic acid (GA), pinoresinol diglucoside (PG) and chlorogenic acid (CA) are three compounds isolated from the bark of the Eucommia tree, which display enormous bioactivities. As a type of plant tissue culture, the hairy root culture system displays prospective application over traditional cell or callus cultures, which are characterized by rapid growth, and stable biochemical and genetic capacity. The present dissertation discusses the establishment and chemical analysis of E. …

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Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover Jan 2007

Wet And Dry Aging Of Polymer-Asphalt Blends: Chemistry And Performance, Ionela Chiparus Glover

LSU Doctoral Dissertations

A PG 76-22 Polymer Modified Asphalt Cement composition was subjected in the laboratory to accelerated aging using both a standard Thin Film Oven Test and a Pressure Aging Vessel. Conditions simulating wet atmospheres (PAV in saturated water vapors) as well as very long service terms (multiple dry and wet PAV operations) were studied. A Rotating Cylinder Aging Test has been employed as an alternate asphalt aging technique using the same PMAC composition in order to observe the initial phases of the oxidative aging process. The data provided by this technique was correlated with the actual aging in the field of …

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Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang Jan 2007

Synthesis Of Quaternary Dendronized Cellulose Derivatives And Their Potential Biological Applications, Changde Zhang

LSU Doctoral Dissertations

In this dissertation, novel dendronized cellulose derivatives with biodegradable backbones were created by using sodium carboxymethyl cellulose (CMC) as the starting material. CMC was first transformed into its corresponding tetrabutyl ammonium salt, which reacted with 2-chloro-N-methylpyridinium iodide (CMPI) to produce an activated ester of [2-(N-methyl pyridium) carboxymethyl cellulose] iodide (MPCMCI). The reaction of MPCMCPI and di-tert-butyl 4-[2-(ter-butoxycarbonyl)ethyl]-4-aminoheptanedicarboxylate (BA) produced a new derivative with BA dendron elaborated on cellulose backbone (CMCBA). The degree of substitution (DS) of CMCBA was adjusted by controlling the relative concentration of CMPI and by choosing CMC with different DS or different molecular weights. Thermogrametric analysis (TGA) …

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Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu Jan 2007

Synthesis And Evaluation Of Derivatives And Analogs Of Xanthene Dyes, Xiangyang Xu

LSU Doctoral Dissertations

Xanthene dyes are one of the oldest synthetic dyes. Fluorescein was first synthesized by von Baeyer in 1871. Since its discovery, it has been extensively studied. Fluorescein can exist as four different ionic forms (cationic form, neutral form, monoanionic form and dianionic form). Under physiological conditions (pH 7.4), fluorescein mainly exists as the dianionic form which grants it large quantum yield and excellent solubility in water. This renders fluorescein and its derivatives useful for studies in biological media. Cysteine (Cys) and homocysteine (Hcy) are of the few amino acids which contain sulfur and both of them are believed to be …

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Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang Jan 2007

Stereochemical And Regiochemical Trends In The Selective Spectrophotometric Detection Of Biological Molecules, Shan Jiang

LSU Doctoral Dissertations

Useful mechanistic studies to date concerning sugar detection by arylboronic acid chemosensors have mainly involved the elucidation of equilibrium constants and the role of boron-nitrogen interactions in signal transduction. However, several discreet sugarboronate complexes exist in solution. This is due to the complex equilibria between isomeric species of even the simplest monosaccharides. Relatively few reports have been devoted to a systematic study of the structures of each of the corresponding individual sugar-boronate complexes. We have investigated some of the precise regio- and stereochemical features of the various equilibrating sugar isomers that induce selective signal transduction. As a result of this …

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Synthesis And Properties Of Isoporphyrins And Related Derivatives For Application In Photodynamic Therapy, Sandra Celinah Mwakwari Jan 2007

Synthesis And Properties Of Isoporphyrins And Related Derivatives For Application In Photodynamic Therapy, Sandra Celinah Mwakwari

LSU Doctoral Dissertations

Isoporphyrins are tautomers of porphyrins with an interrupted macrocyclic conjugation owing to the presence of a sp3 hybridized meso-carbon. Due to their absorption at long wavelengths (~800nm), isoporphyrins are potential candidates as photosensitizers in photodynamic therapy (PDT), a ternary modality of cancer treatment. They are also of biological interest due to their unique redox properties among porphyrin derivatives and could be a new class of near-IR dyes. Isoporphyrins are known to be unstable with respect to transformation back to the fully conjugated porphyrin chromophore except when the meso-carbon is geminally substituted and for this reason a detailed study of this …

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Design, Synthesis, And Conformational Studies Of Peptides Containing α,α-Disubstituted Amino Acids, Jia Wang Jan 2007

Design, Synthesis, And Conformational Studies Of Peptides Containing α,α-Disubstituted Amino Acids, Jia Wang

LSU Doctoral Dissertations

Cα,α-disubstituted amino acids (ααAAs) are widely utilized to conformationally constrain peptides. Several pentapeptides containing dipropylglycine (Dpg) at alternating positions and their α-amino acid counterpart L-norvaline (Nva) analogues were synthesized to fully investigate the impact of Dpg on peptide backbone structure in aqueous solution. CD, VCD and NMR spectral analysis suggest that Dpg containing peptides adopt more ordered structures relative to their Nva containing analogues. The central residues (Ala, Thr, Tyr, Val) and the charged side-chains of Glu and Lys play important roles in the degree of peptide folding. Hydrophobic and branched residues (Val, Tyr) at the …

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Copper(Ii) Oxide Mediated Formation And Stabilization Of Combustion Generated Persistent Free Radicals, Hieu Truong Jan 2007

Copper(Ii) Oxide Mediated Formation And Stabilization Of Combustion Generated Persistent Free Radicals, Hieu Truong

LSU Doctoral Dissertations

Biologically damaging semiquinone-type radicals have been reported in cigarette smoke, their likely origin being hydroquinone (HQ) and catechol (CT) molecular precursors contained by the tobacco. Since other biomass contains HQ and CT-type species, it is likely that combustion of other biomass will also form semiquinone-type radicals. All hydrocarbon fuels will form phenol and substituted phenol that can form substituted phenoxyl radicals. Because each of these radicals has the potential to be environmentally persistent and biologically active, their formation and stabilization from various molecular precursors was studied with the focus on surface-bound radicals formed in association with combustion-generated fly-ash particles. Comprehensive …

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The Effects Of Trawling And Habitat Use On Red Snapper And The Associated Community, Robert Joseph David Wells Jan 2007

The Effects Of Trawling And Habitat Use On Red Snapper And The Associated Community, Robert Joseph David Wells

LSU Doctoral Dissertations

The primary impediment to the recovery of Gulf of Mexico (GOM) red snapper is believed to be high levels of bycatch of age 0 and age 1 individuals in shrimp trawls. Thus, conservation of GOM red snapper involves evaluating both habitat-specific function and effects of shrimp trawls on red snapper and the associated benthic ecosystem. The two goals of this study were to evaluate the effects commercial shrimp trawls have on juvenile red snapper life history parameters, on associated fish and invertebrate communities and their habitat, and to identify essential fish habitat (EFH) for red snapper by applying all four …

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Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli Jan 2007

Multiplicative Renormalization Method For Orthogonal Polynomials, Suat Namli

LSU Doctoral Dissertations

To study the orthogonal polynomials, Asai, Kubo and Kuo recently have developed the multiplicative renormalization method. Motivated by infinite dimensional white noise analysis, it is an alternative to the computational part of the classical Gram-Schmidt process to find the orthogonal polynomials for a given measure. Instead of finding the orthogonal polynomials recursively as described in the Gram-Schmidt process, one analyzes different types of generating functions systematically in order to obtain polynomials after power series expansion. This work also produces the Jacobi-Szego parameters easily and paves the way for the study of one-mode interacting Fock spaces related to these parameters. They …

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The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree Jan 2007

The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree

LSU Doctoral Dissertations

Efforts to improve the technology for DNA analyses stimulated the work presented here to develop a series of fluorescent probes that would aid in the increased multiplexing capabilities allowing the ability to detect multiple targets in a single measurement. Typically, spectral discrimination has been used to identify each DNA fragment in sequencing or diagnostic applications by means of unique emission properties from several labeling dyes. This has been accomplished with labels that fluoresce in the visible region. The limitations with these dyes is the broad emission profile making discrimination difficult, high intrinsic biological fluorescence and structural differences of the dyes …

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Probing The Association Behavior Of Hydrophobic Organic Compounds With Dissolved Humic Materials, Hadi M. Marwani Jan 2007

Probing The Association Behavior Of Hydrophobic Organic Compounds With Dissolved Humic Materials, Hadi M. Marwani

LSU Doctoral Dissertations

The association mechanism between hydrophobic organic compounds (HOC) and dissolved humic materials (DHM) has continued to be one of the interesting areas in environmental applications. The goal of the research reported in this dissertation is to investigate the association behavior of HOC with DHM. The first part of this research involves steady-state fluorescence measurements of these multi-component systems to study the effect of DHM content on the association mechanism of HOC, in particular using pyrene as a model. Results showed that steady-state fluorescence alone may not provide enough information about the quenching mechanism of pyrene with DHM. Lifetime based fluorescence …

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A Comparison Of Channel Morphology, Marsh Elevation, And Biological Processes In Natural And Dredged Tidal Salt Marshes In Louisiana, Jennifer S. Spicer Jan 2007

A Comparison Of Channel Morphology, Marsh Elevation, And Biological Processes In Natural And Dredged Tidal Salt Marshes In Louisiana, Jennifer S. Spicer

LSU Doctoral Dissertations

Channel networks in tidal marshes serve as conduits for the exchange of water between the estuary and the marsh surface and form the spatial structure that regulates the flow of organisms, materials, and energy throughout the marsh system. Canal dredging creates channels with distinct linear shapes, and the artificial levee created from the dredged material creates ‘spoil banks’ along either side of the channel edge. Differences in morphology and adjacent marsh surface elevation between natural and dredged channel systems have not been well quantified, but may have important implications for the functioning of tidal channels as habitat for marsh-dependent species. …

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Chiral Analyses Using Molecualr Micelles And Multiple Regression Modeling In Chromatographic And Spectroscopic Methods, Alicia Williams Snearl Jan 2007

Chiral Analyses Using Molecualr Micelles And Multiple Regression Modeling In Chromatographic And Spectroscopic Methods, Alicia Williams Snearl

LSU Doctoral Dissertations

Multiple regression modeling techniques allow for rapid and accurate prediction of migration times and resolution values for micellar electrokinetic chromatography (MEKC) as well as the development of quick screening methods using steady-state fluorescence spectroscopy. All studies reported in this dissertation include optimization of calibration models and predictions of dependent variables by the use of validation samples. The root-mean-square percent relative error (RMS%RE) is used as a figure of merit for characterizing the performance of the calibration models. MEKC separations of achiral and chiral analytes were performed using an achiral molecular micelle, poly(sodium N-undecylenic sulfate), and chiral molecular micelles, poly(sodium N-undecanoyl-L-leucylvalinate) …

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Shear Responses Of Poly(Ethylene Oxide)-Laponite Nanocomposite Hydrogels, Elena Loizou Jan 2007

Shear Responses Of Poly(Ethylene Oxide)-Laponite Nanocomposite Hydrogels, Elena Loizou

LSU Doctoral Dissertations

This research seeks to understand the structure and shear responses of poly(ethylene oxide)-Laponite nanocomposite hydrogels and to relate the macroscopic physical properties to the nanoscopic structural changes. Understanding that relationship is necessary, in order to tailor material properties to specific applications. Information on the structure at rest on multiple length scales was obtained by combining microscopic and neutron scattering techniques. The structural changes that occur in response to a shear field were explored using rheology and neutron scattering. These structures were examined as a function of polymer molecular weight, polymer and clay concentrations, and sample preparation method. While the sample …

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Tourmalinities In Neoproterzoic Metaevaporitic Deposit Of Duruchas Formation, Damar Belt, Central Namibia, Haiting Sun Jan 2007

Tourmalinities In Neoproterzoic Metaevaporitic Deposit Of Duruchas Formation, Damar Belt, Central Namibia, Haiting Sun

LSU Doctoral Dissertations

Tourmalinites from a well-developed meta-evaporite sequence in the Neoproterozoic Duruchaus Formation of central Namibia contain tourmalines with chemical and textural features that are excellent recorders of their environment of formation. Unlike most other meta-evaporitic deposits, this tourmalinite locality exhibits only minor deformation. The tourmalinites form as finely laminated units ca. 1 m thick within a sequence of quartzites, mica schists, dolomitic marbles, and carbonate breccias. Well-preserved pseudomorphs are considered to replace a variety of evaporitic minerals. The meta-sedimentary rocks of the Duruchaus Formation have been interpreted as representing lacustrine, playa lake, fluvial, and non-marine evaporite deposition in an intracontinental rift …

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Structural Manipulation Of Pyrrole-Terminated Dendrimers To Create A More Efficient Encapsulation/Release System, Henry Wiggins Jan 2007

Structural Manipulation Of Pyrrole-Terminated Dendrimers To Create A More Efficient Encapsulation/Release System, Henry Wiggins

LSU Doctoral Dissertations

This work demonstrates the ability to manipulate the structure of pyrrole-terminated dendrimers by modifying solution conditions which directly affects their encapsulation properties. Investigations were conducted using FTIR and 2D NMR to determine the location of end groups. NMR relaxation studies were conducted at various temperatures and different solution pH to gain an understanding of the relative mobility and rigidity of different areas of the dendrimer. It was found that that the release properties were affected by the solution pH and the presence of salt. Further the effectiveness of retaining molecular guests by oligo-pyrrole terminated dendrimers with a range of oligomer …

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Elementary Reactions Involved In Pollutant-Forming Mechanisms, Cheri Ann Mcferrin Jan 2007

Elementary Reactions Involved In Pollutant-Forming Mechanisms, Cheri Ann Mcferrin

LSU Doctoral Dissertations

The reactions of the hydroxyl radical (OH) with molecular chlorine (Reaction 1), methane (Reaction 2), and propane (Reaction 3) have been studied experimentally using a pulsed laser photolysis/pulsed-laser-induced fluorescence technique over wide ranges of temperatures (297-826, 298-1009, and 296-908 K, respectively) and at pressures between 6.68 and 24.15 kPascals. The rate coefficients for these reactions exhibit no dependence on pressure and exhibit positive temperature dependences that can be represented with modified three-parameter Arrhenius expressions within their corresponding temperature ranges: k1 = 3.59 x 10-16T1.35exp(-745K/T)cm3molecule-1sec-1, k2 = 3.82 x 10-19T2.38 exp(-1136K/T)cm3molecule-1sec-1, and k3 = 6.64 x 10-16T1.46 exp(-271K/T)cm3molecule-1sec-1. For the OH …

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Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk Jan 2007

Lanthanide Complexes As Fluorescent Indicators For Neutral Sugars And Cancer Biomarkers, Onur Alpturk

LSU Doctoral Dissertations

Simple water soluble lanthanum and europium complexes are effective at detecting neutral sugars as well as glyco- and phospholipids. In solutions at physiologically relevant pH the fluorescent lanthanum complex binds neutral sugars with apparent binding constants comparable to those of arylboronic acids. Interference from commonly occurring anions is minimal. The europium complex detects sialic acid-containing gangliosides at pH 7.0 over an asialoganglioside. This selectivity is attributed, in large part, to the cooperative complexation of the oligosaccharide and sialic acid residues to the metal center, based on analogous prior studies. In MeOH, lysophosphatidic acid (LPA), a biomarker for several pathological conditions …

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Xanthene/Benzoxanthene Dyes: Novel Synthetic Metholologies, Applications In Molecular Recognition, Cellular Imaging And The Design Of A Tunable White (Rgb) Light Emitter, Youjun Yang Jan 2007

Xanthene/Benzoxanthene Dyes: Novel Synthetic Metholologies, Applications In Molecular Recognition, Cellular Imaging And The Design Of A Tunable White (Rgb) Light Emitter, Youjun Yang

LSU Doctoral Dissertations

My graduate work has focused on the development of new fluorophore materials towards addressing several interdisciplinary research problems. Selective detection of sialic acid via a boron-amide interaction. Concentration changes of sialic acid can be monitored ratiometrically in the visible region using a boronic acid based chemosensor. The technique shows great promise for the detection of sialic acid, a critical cell surface residue involved in cancer, graft rejection and virulence in certain bacteria. There is no interference from commonly occurring oligosaccharides, aminosugars and most carboxylic acid-containing compounds. Improved synthetic methodology and studies of novel molecular probe architectures. I have developed a …

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Syntheseses [Sic] And Evaluation Of Porphyrin Derivatives For Applications In Medicine And In Material Science, Erhong Hao Jan 2007

Syntheseses [Sic] And Evaluation Of Porphyrin Derivatives For Applications In Medicine And In Material Science, Erhong Hao

LSU Doctoral Dissertations

Chapter 1 presents a concise introduction to porphyrins, especially on the synthesis of meso-tetraphenylporphyrins, which were synthesized during the course of my research and were used for further purposes in the following chapters. Chapter 2 describes the synthesis of a series of cobaltacarborane-porphyrin conjugates for the boron neutron capture therapy (BNCT) of tumors. Using an efficient and high yield ring-opening reaction, N-substituted porphyrins were also synthesized. The spectroscopic and structural properties of these compounds are presented. These high percentage boron and amphiphilic compounds are promising boron delivery agents for BNCT (prelimary cellular studies using some of these compounds have been …

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Wood Liquefaction In The Presence Of Phenol With A Weak Acid Catalyst And Its Potential For Novolac Type Wood Adhesives, Hui Pan Jan 2007

Wood Liquefaction In The Presence Of Phenol With A Weak Acid Catalyst And Its Potential For Novolac Type Wood Adhesives, Hui Pan

LSU Doctoral Dissertations

Wood liquefaction was conducted using phenol as a reagent solvent with oxalic acid as a catalyst. A series of studies were done on liquefied wood, liquefied wood residues, novolac-type liquefied wood resins, and bio-composites fabricated from liquefied wood resin. The results of the liquefied wood residue characterization revealed that the liquefaction reactions conducted in different reaction vessels underwent different liquefaction mechanisms. The crystallinity indexes of the liquefied wood residues were higher than that of the original wood, indicating that the amorphous lignin was the most susceptible component in wood to the liquefaction reaction. Fe2+ and Fe3+ ions were found to …

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Backward Stochastic Navier-Stokes Equations In Two Dimensions, Hong Yin Jan 2007

Backward Stochastic Navier-Stokes Equations In Two Dimensions, Hong Yin

LSU Doctoral Dissertations

There are two parts in this dissertation. The backward stochastic Lorenz system is studied in the first part. Suitable a priori estimates for adapted solutions of the backward stochastic Lorenz system are obtained. The existence and uniqueness of solutions is shown by the use of suitable truncations and approximations. The continuity of the adapted solutions with respect to the terminal data is also established. The backward stochastic Navier-Stokes equations (BSNSEs, for short) corresponding to incompressible fluid flow in a bounded domain $G$ are studied in the second part. Suitable a priori estimates for adapted solutions of the BSNSEs are obtained …

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Computing And Analyzing Gravitational Radiation In Black Hole Simulations Using A New Multi-Block Approach To Numerical Relativity, Ernst Nils Dorband Jan 2007

Computing And Analyzing Gravitational Radiation In Black Hole Simulations Using A New Multi-Block Approach To Numerical Relativity, Ernst Nils Dorband

LSU Doctoral Dissertations

Numerical simulations of Kerr black holes are presented and the excitation of quasinormal modes is studied in detail. Issues concerning the extraction of gravitational waves from numerical space-times and analyzing them in a systematic way are discussed. A new multi-block infrastructure for solving first order symmetric hyperbolic time dependent partial differential equations is developed and implemented in a way that stability is guaranteed for arbitrary high order accurate numerical schemes. Multi-block methods make use of several coordinate patches to cover a computational domain. This provides efficient, flexible and very accurate numerical schemes. Using this code, three dimensional simulations of perturbed …

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Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan Jan 2007

Exploring The Quark-Gluon Content Of Hadrons: From Mesons To Nuclear Matters, Hrayr Hamlet Matevosyan

LSU Doctoral Dissertations

Even though Quantum Chromodynamics (QCD) was formulated over three decades ago, it poses enormous challenges for describing the properties of hadrons from the underlying quark-gluon degrees of freedom. Moreover, the problem of describing the nuclear force from its quark-gluon origin is still open. While a direct solution of QCD to describe the hadrons and nuclear force is not possible at this time, we explore a variety of developed approaches ranging from phenomenology to first principle calculations at one or other level of approximation in linking the nuclear force to QCD. The Dyson Schwinger formulation (DSE) of coupled integral equations for …

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Synthesis And Functionalizations Of Tetrapyrrole Derivatives, Lijuan Jiao Jan 2007

Synthesis And Functionalizations Of Tetrapyrrole Derivatives, Lijuan Jiao

LSU Doctoral Dissertations

Chapter 1 of this Dissertation presents a brief overview of the history of tetrapyrrole derivatives and of their fundamental properties. Overviews of porphyrins, benzoporphyrins, chlorins and porphycenes are presented. Work presented in Chapter 2 through Chapter 4 mainly focuses on the syntheses and functionalization of chromophore-extended porphyrin derivatives. Several new synthetic routes for the syntheses and functionalizations of extended porphyrins either at the β-position or at the meso-position of porphyrin are developed. From these improved synthetic routes, the regio-selective syntheses of porphyrin derivatives are described. Chapter 2 mainly focuses on the syntheses of β,β'-fused methylenepropanoporphyrins and related porphyrin dimers. Chapter …

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